Clinical and electromyographic studies of postpoliomyelitis muscular atrophy

Eleven patients with progressive weakness following polio (postpoliomyelitis muscular atrophy syndrome) were compared electromyographically with nine patients who had stable strength following polio. Abnormalities included (1) abnormal motor unit characteristics in many muscles indicating widespread loss of motor neurons and reinnervation in muscles, including many not clinically affected by the polio; (2) prevalent spontaneous denervation potentials; and (3) abnormal single-fiber electromyographic jitter. These electromyographic abnormalities were similar in progressive and stable postpoliomyelitis patients even when muscles were separated by strength, stability, age and duration of the postpoliomyelitis state. Postpoliomyelitis muscular atrophy appears to be the clinically apparent end of the spectrum of abnormalities existing in all postpoliomyelitis patients.

Poliomyelitis

1996 is polio awareness year. This paper reviews the clinical syndrome of acute paralytic poliomyelitis and its sequelae. We discuss epidemiological studies of the syndrome of late functional deterioration many years after the acute infection and the current hypotheses of the pathophysiology of such disorders. Recent evidence has suggested that potentially treatable factors may be implicated in the majority of such patients and it is therefore important to exclude such disorders before attributing late functional deterioration to progressive post-polio muscular atrophy.

Use of monoclonal antibodies to identify serotypes of enterovirus isolates

Nonpoliovirus enteroviruses cause a variety of diseases that are common in young children and adults. The "gold standard" for laboratory diagnosis of enteroviruses is cell culture isolation, followed by serotype identification by neutralization assay. These procedures are time-consuming and expensive. Rapid serotype identification of enteroviruses is important in differentiating nonpoliovirus enterovirus pathogens from vaccine strain polioviruses that can be shed for some time after vaccination. In the present investigation, we evaluated a rapid method for serotype identification of enteroviruses by indirect immunofluorescence assay (IFA) using commercially available monoclonal antibodies for polioviruses, coxsackieviruses type B, and six serotypes of commonly circulating echoviruses. Of 291 isolates of enteroviruses included in the study, 95 were polioviruses and 196 were nonpoliovirus enteroviruses. Two hundred thirty-four of these (38 polioviruses and 196 nonpoliovirus enteroviruses) were consecutively grown in the laboratory over a 5-year period. IFA identified the serotypes of 74% of the consecutive isolates and 71% of all enterovirus isolates by yielding a positive staining result. The levels of agreement in the identification of the enterovirus group between IFA and neutralization tests were 92% for consecutively grown isolates and 85% for all enterovirus isolates. The sensitivity of the IFA for the detection of viruses for which specific monoclonal antibodies were applied was 73% for polioviruses, 85% for coxsackieviruses type B, and 94% for echoviruses. Specificity was near 100% for polioviruses and coxsackieviruses type B and 94% for echoviruses. We conclude that IFA can be helpful as a preliminary test for serotype identification of enteroviruses. The results are most accurate when the test identifies the isolate as a poliovirus.

Selective isolation of poliovirus in recombinant murine cell line expressing the human poliovirus receptor gene

Sixty-eight laboratory strains representing 49 enterovirus, 10 adenovirus, and 3 reovirus serotypes were inoculated in a recombinant murine cell line expressing the human poliovirus receptor gene (L alpha cells). Only polioviruses caused cytopathic effect over a 10-day period. Likewise, only polioviruses were isolated, by use of L alpha cells, from 168 fecal specimens from children from developing countries. These results suggest that the recombinant L alpha cells can be used for selective isolation of poliovirus from clinical specimens.

New neuromuscular symptoms in patients with old poliomyelitis: a three-year follow-up study

Fourteen survivors of paralytic poliomyelitis experienced new symptoms after years of stability. Seven patients had lost functional capacity, with joint pain, instability and recurrent falls, but were again stable and remained essentially unchanged during a 3-year follow-up period. Seven others had late postpoliomyelitis muscular atrophy (PPMA) with new weakness, wasting, fasciculations and myalgia in muscles originally spared or seemingly recovered. Muscle biopsy from newly affected muscles showed new and chronic denervation with interstitial inflammation in 3 patients. Antibody titers to poliomyelitis virus were not elevated in the CSF, but oligoclonal IgG bands were found in 3 PPMA patients. During the 3-year follow-up period, PPMA patients showed signs of slow progression which continued to be focal. It is concluded that the new symptoms in postpolio patients may be musculoskeletal and relatively stable, or due to a slowly progressive, focal, and apparent benign new motor neuron deterioration.

Poliomyelitis-like syndrome associated with Epstein-Barr virus infection

A 20-month-old male presented with an acute clinical syndrome resembling poliomyelitis, characterized by a flaccid monoplegia, areflexia of the involved limb, and preserved sensation. Electrophysiologic studies supported a neuronopathic localization involving the anterior horn cells. Although laboratory evidence for a poliovirus infection was absent, serologic and polymerase chain reaction studies documented an active central nervous system infection with Epstein-Barr virus, indicating that a poliomyelitis-like syndrome may be produced by infectious agents other than enteroviruses.

The role of supplementary environmental surveillance to complement acute flaccid paralysis surveillance for wild poliovirus in Pakistan - 2011-2013

Background

More than 99% of poliovirus infections are non-paralytic and therefore, not detected by acute flaccid paralysis (AFP) surveillance. Environmental surveillance (ES) can detect circulating polioviruses from sewage without relying on clinical presentation. With extensive ES and continued circulation of polioviruses, Pakistan presents a unique opportunity to quantify the impact of ES as a supplement to AFP surveillance on overall completeness and timeliness of poliovirus detection.

Methods

Genetic, geographic and temporal data were obtained for all wild poliovirus (WPV) isolates detected in Pakistan from January 2011 through December 2013. We used viral genetics to assess gaps in AFP surveillance and ES as measured by detection of ‘orphan viruses’ (≥1.5% different in VP1 capsid nucleotide sequence). We compared preceding detection of closely related circulating isolates (≥99% identity) detected by AFP surveillance or ES to determine which surveillance system first detected circulation before the presentation of each polio case.

Findings

A total of 1,127 WPV isolates were detected by AFP surveillance and ES in Pakistan from 2011–2013. AFP surveillance and ES combined exhibited fewer gaps (i.e., % orphan viruses) in detection than AFP surveillance alone (3.3% vs. 7.7%, respectively). ES detected circulation before AFP surveillance in nearly 60% of polio cases (200 of 346). For polio cases reported from provinces conducting ES, ES detected circulation nearly four months sooner on average (117.6 days) than did AFP surveillance.

Interpretation

Our findings suggest ES in Pakistan is providing earlier, more sensitive detection of wild polioviruses than AFP surveillance alone. Overall, targeted ES through strategic selection of sites has important implications in the eradication endgame strategy.

MRI in acute poliomyelitis

MRI can be used in the diagnosis of anterior horn infection and for assessing the extent of disease. There are no specific MRI signs to differentiate between the various possible pathogens. This is demonstrated in the present case of poliomyelitis, in which MRI of the spine played an important role in establishing the diagnosis.

Immunological abnormalities in the syndrome of poliomyelitis-like illness associated with acute bronchial asthma (Hopkin's syndrome)

In recent years an unusual syndrome of poliomyelitis-like illness, associated with acute bronchial asthma, has been reported from different parts of the world. A further 3 cases are described in this paper. Although the condition resembles poliomyelitis in most respects, particularly with regard to the severe permanent residual weakness usually observed, consistent evidence of a viral aetiology has not been forthcoming. Tests of immune function suggested the presence of varying degrees of nonspecific immune deficiency in our 3 patients, but evidence of viral invasion was inconclusive. It is suggested that a combination of immune deficiency with the stress of the acute asthma attack rendered the patients susceptible to invasion of the anterior horn cells by a viral agent, which may have been of external origin, or may have existed in a latent form within the host.

Management of postpolio syndrome

Recent research has shed light on the pathogenesis of the postpolio syndrome and has helped explain its symptoms and the rationale for management. The aim of this article is to familiarize physicians with this syndrome. The history, acute infection, definition, and diagnosis are discussed, as well as the various symptoms and their management. People with postpolio syndrome can educate health professionals about this condition and can help others inflicted with this syndrome. Thus far, no cure is available. A correct diagnosis is important, and the physician must realize that severe comorbidities tend to afflict people with this syndrome. Numerous management options are available to help these people enjoy a high quality of life.

Amyotrophic lateral sclerosis and other motor neuron diseases

The anterior horn cell diseases, with the exception of polio, are progressive degenerative diseases of the motor neurons. These disorders include SMA types I to III in children and familial and sporadic ALS and its variants (PMA, PLS, and PBP), Kennedy's disease, and SMA type IV in adults. The electrodiagnostic study is a crucial step in the diagnostic process for all of these disorders. In general, motor NCS may be normal or reveal low CMAP amplitudes with relatively normal conduction velocities. Sensory NCS, except in the case of Kennedy's disease, are normal. The NEE is notable for the often abundant presence of abnormal spontaneous activity, including fibrillation potentials and positive sharp waves, fasciculation potentials, and complex repetitive discharges. Motor unit morphology is abnormal, with polyphasic motor units and large amplitude and duration MUAPs when the disease is slowly progressive. Recruitment in affected muscles is reduced with abnormally rapidly firing motor units. To diagnose a widespread disorder of the motor neurons, abnormalities must be present in multiple muscles with different nerve root and peripheral nerve innervation in multiple limbs. The Lambert Criteria and the El Escorial Criteria are the two most widely accepted sets of electrodiagnostic criteria for ALS. The electrodiagnostic diagnosis must be supported by appropriate history and physical examination findings and the exclusion, via neuroimaging and laboratory testing, of other diseases that may mimic a generalized disorder of the motor neurons.

Oligonucleotide probes for the specific detection of the wild poliovirus types 1 and 3 endemic to Brazil

Synthetic oligodeoxynucleotide probes, 21-23 nucleotides in length, were prepared which specifically hybridize to the genomes of the wild type 1 and 3 polioviruses currently endemic to the northeastern region of Brazil. The probes are complementary to sequences near the 5'-terminus of the VP1 gene that differ substantially among genetically distant polioviruses but are largely conserved among related isolates. The probes have been routinely used in the laboratory surveillance of poliomyelitis cases in Brazil, permitting direct, rapid identification of the indigenous wild polioviruses by dot-blot hybridization.

Neuralgic amyotrophy: criteria for diagnosis and a clinical with electromyographic study of 21 cases

Twenty-one cases of neuralgic amyotrophy referred for diagnosis and for electromyography were studied. The criteria used for diagnosis included pain, wasting and paralysis of shoulder girdle muscles, the absence of a compressive or traumatic lesion, spontaneous full or partial recovery and electromyographic findings of denervation or reduced numbers of functioning motor units of the muscles involved. Pain was usually sudden in onset and preceded paralysis. The commonest muscles involved were the deltoid, supraspinatus, infraspinatus and biceps. Sensory changes were minimal. Recovery was the rule and repeat electromyogram after full clinical recovery was normal. The common diagnostic difficulties were excluding poliomyelitis in children, trauma in adults and cervical spondylosis in the elderly. The atypical manifestations need to be recognised in this condition, the aetiology of which is unknown in the majority of cases.

PCR diagnosis of primary herpesvirus type I in poliomyelitis-like paralysis and respiratory tract disease

Successful and rapid recovery of HSV-1 DNA from the cerebrospinal fluid after amplification by polymerase chain reaction was obtained in a 7-year-old boy with subtotal and permanent upper extremity paralysis with rapid onset and magnetic resonance imaging evidence of cervical cord involvement. Early administration of intravenous acyclovir probably limited neuronal loss. The clinical course and outcome of this disorder best conformed with what has been described as poliomyelitis-like paralysis associated with respiratory tract infection (Hopkins syndrome).

A complement fixation test for poliomyelitis

A macroscopic (tube) complement fixation test for poliomyelitis, using infected tissue culture fluids, is described. The test was applied to 27 individuals with a clinical diagnosis of poliomyelitis. In 18 patients it was possible to make a laboratory diagnosis of poliomyelitis on the basis of a rise in complement-fixing antibody titer and in 4 others on the basis of a high stationary antibody titer. One individual gave a high and equal antibody response to two virus types, 3 others had no detectable antibody, and 1 appeared not to have poliomyelitis. Heterotypic reactions were encountered, but gave little difficulty in interpreting homologous responses. In those patients from whom a virus had been recovered, the serologic findings corresponded to the virus type recovered. The possible occurrence of dual infections with the viruses of poliomyelitis and Western equine and St. Louis encephalitis is discussed.

Nonpoliovirus poliomyelitis simulating Guillain-Barré syndrome

BACKGROUND

Paralytic poliomyelitis due to the wild-type poliovirus has been eradicated in the United States because of effective immunization programs. In the postvaccination era, most cases are caused by other RNA viruses, such as coxsackievirus or echovirus. The condition usually begins with a fever and upper respiratory tract or gastrointestinal tract symptoms that progress to a "paralytic" phase characterized by limb weakness, areflexia, and, occasionally, respiratory failure that superficially resemble Guillain-Barré syndrome.

OBJECTIVE

To describe 2 patients with nonpoliovirus poliomyelitis and highlight the findings on magnetic resonance imaging of the spinal cord to distinguish these cases from variants of Guillain-Barré syndrome.

DESIGN AND SETTING

Case series from an academic medical center.

PATIENTS

Following a viral illness, the patients, aged 35 and 50 years, had painless, progressive, asymmetrical weakness in the arms followed by respiratory failure in one patient, and generalized limb weakness in the other patient, reaching a nadir in 1 week. Both patients had fevers but no signs of meningitis at onset. Tendon reflexes were absent or reduced in affected regions. The cerebrospinal fluid findings were as follows: mononuclear leukocyte counts of 100 000 cells/mm(3) and 700 000 cells/mm(3), respectively, and the protein level was above 10 g/dL in both patients. Compound muscle action potential amplitudes were reduced in some nerves with active denervation in clinically affected muscles, and F-responses were absent but there were no other demyelinating features. Magnetic resonance imaging showed discrete T2-weighted signal changes of the ventral horns of the spinal cord, and one had elevated coxsackievirus titers in the serum. There was little recovery and significant atrophy in weak muscles after 3 years.

CONCLUSIONS

The poliomyelitis syndrome still occurs in adults in developed countries. It has superficial similarities to a motor axonal variant of Guillain-Barré syndrome but can be distinguished by clinical, cerebrospinal fluid, and, perhaps specifically, magnetic resonance imaging characteristics.

Rapid diagnosis of poliovirus infection by PCR amplification

A single-tube, single-primer-set reverse transcription-PCR assay was developed for the rapid detection of polioviruses in infected tissue culture fluids and clinical materials. The poliovirus-specific PCR primers are located in the VP1-2A region of the poliovirus genome. They generate a 290-bp product and can be used in duplex reactions with general enterovirus primers. The primers span the region used for genotype determination, so that genotype analysis of wild-type polioviruses can be performed by direct sequencing of the PCR products. Of 125 virus isolates typed as polioviruses by neutralization assays, 125 (100%) were also positive by PCR, and of 38 isolates typed as non-polio enteroviruses by conventional techniques, 38 (100%) were also negative by PCR. The assay described here is rapid, highly sensitive, and specific and has clinical applicability in the diagnosis of poliovirus infections.

Late sequelae of paralytic poliomyelitis: a clinical and electromyographic study

A prospective study was carried out on 24 volunteers who had suffered from paralytic poliomyelitis up to 51 years earlier. A quantitative EMG was carried out in each subject. Grossly raised mean amplitudes of the interference patterns were found in many strong muscles as well as in weak muscles. Such muscles frequently showed "contraction fasciculation", a manifestation of loss of normal small motor units. In many subjects the clinical and EMG evidence of chronic partial denervation were more widespread than the subjects had realised. It is suggested that if, with advancing age, minor damage occurs to the peripheral nervous system and the complement of motor neurones is already depleted by poliomyelitis, there will be an exaggerated response with increase in the lower motor neurone signs.